1. Field of the Invention
The present invention relates to a semi-automatic analyzing apparatus using an analyzer for analyzing a solution or liquid, in particular to an analyzing apparatus in which drops of test solution and standard solution are individually spotted on elements formed on a plate member and a substance concentration such as an ion concentration of the test solution is detected by a signal detected on the basis of the spotted solutions.
2. Description of the Prior Art
As an example of this kind of analyzer, the explanation is made about an ionic activity measuring analyzer disclosed in the Japanese Patent Laid Open 62-165147 with reference to FIGS. 1 to 3.
FIGS. 1 and 2 show a perspective view and a sectional view of a driving mechanism portion for shifting a plate member to a predetermined measurement position and FIG. 3 shows an exploded perspective view of plate members used in the analyzer.
As shown in FIG. 3, the plate member 200 comprise a water impermeable upper substrate 201 having three pairs of solution receiving holes 211-212, 213-214 and 215-216 for receiving a test solution and standard solution in order to measure three kinds of ion concentrations (such as Na.sup.+, K.sup.+ and Cl.sup.-); a lower supporting frame 231; and three pairs of strip shaped electrodes 221-222, 223-224 and 225-226 provided between the substrate 201 and the lower supporting frame 231, in other words, provided under the substrate 201 corresponding to the positions of the respective solution receiving holes 211 to 216 and on the lower supporting frame 231. In a predetermined portion on the underside surface of the lower supporting frame 231, there are depicted bar codes (not shown) for representing test items of the plate member 200 and batch data of the plate member 200 In addition, although there are provided pouring members on the substrate 201 for charging the test solution into the solution receiving holes 211, 213 and 215 and for charging the standard solution into the solution receiving holes 212, 214 and 216, the explanation thereof is omitted.
In this plate member 200, when a drop of the test solution is spotted in the solution receiving hole 211 and a drop of the standard solution is spotted in the solution receiving hole 212, there is generated electric power based on the ionic activities contained in the respective test and standard solutions disposed in the solution receiving holes 211 and 212 so that there occurs potential different between the electrodes 221 and 222 corresponding to the solution receiving holes 211 and 212 respectively. Therefore, by measuring the above difference of potential between the electrodes 221 and 222, the Na.sup.+ ion concentration of the test solution can be detected on the basis of calibrations predetermined by using a known Na.sup.+ ion solution.
Next, the structure and operation of the conventional analyzer mentioned above are explained with reference to FIGS. 1 and 2. Under the condition that the plate member 200 is set in a setting opening 51a defined in a central portion of a holder 51, there are spotted drops of blood as a test solution for example in the respective solution receiving holes 211, 213 and 215 formed in the plate member 200 and there are spotted drops of standard ion concentration solution of Na.sup.+, K.sup.+ and Cl.sup.- in the solution receiving holes 212, 214 and 216. And when a predetermined button switch (not shown) is turned on, a motor 52 is driven so as to rotate a rod screw 55 by rotating a pair of engaged gears 53 and 54. By this rotation of the rod screw 55, a female screw member 56 engaged with the rod screw 55 as a male screw is shifted to the right direction along the axis of the rod screw 55, whereby a holder shifting table 57 coupled with the female screw 56 as one body is shifted to the right along a pair of guide members 58. On a left surface of a connecting member 59 projected upward from a predetermined portion of the holder shifting table 57, there is fixed a magnet member 60. Similarly, on a right surface of a connecting member 61 projected downward from a predetermined portion of the holder 51, there is fixed a magnet member 62 abutting to the magnet 60. Therefore, when the holder shifting table 57 is shifted, the holder 51 is similarly slid along a pair of guide members 63 due to the attraction between the two magnet members 60 and 62.
In such a manner as described above, the plate member 200 set in the opening of the holder 51 is shifted together with the holder 51, and when the bar code depicted on the underside surface of the lower supporting frame 231 of the plate member 200 is passed by a position above a bar code reading sensor 64, the bar code is read by the bar code reading sensor 64 which is provided in the central portion under the top plate member 72 of the driving mechanism. The batch data of the bar code are used for correcting the calibrations which are applied for measuring an ion concentration of a solution to be described later.
The holder 51 with the plate member 200 set therein is further slid to the right, and when the right edge portion of the holder 51 is abutted to a left side wall of a stopper portion 65a of a plate depressing member 65, the holder 51 is stopped at this position, but since the motor 52 is still being driven, the magnets 60 and 62 for attracting the holder 51 and the holder shifting table 57 are separated from each other so that only the holder shifting table 57 is shifted to the right.
There is situated a probe holder 68 pushed downward by a spring member 67 in a position below the measurement position of the plate member 200 set in the holder 51 when the holder 51 is stopped by abutting to the holder stopper portion 65a and there is fixed a roller 69 attached to the bottom portion of the probe holder 68. On the other hand, in a predetermined portion of the holder shifting table 57, there is provided a cam member 70 having a right side surface 70a sloped with a predetermined degree, and since the sloped side surface 70a of the cam member 70 is abutted to the roller 69 when the holder shifting table 57 is shifted to the right, the roller 69 together with the probe holder 68 are pushed upward. Consequently, six contact pins 71a fixed on the upper surface of the probe holder 68 are inserted through six holes 72a defined in the top plate member 72 so as to be abutted to the respective electrodes 221 to 226 of the plate member 200, thereafter the motor 52 is stopped. In this state, the difference of potential between the drop of the test solution and the drop of the standard solution disposed in the plate member 200 are detected through the six contact pins 71a. The time period from the drop of the solution onto the plate member 200 to the start of the detection of the difference of potential is predetermined to be one minute and the detection of the difference of potential is carried out in about one minute.
When the detection of the difference of potential is completed, the motor is reversed and the holder shifting table 57 is slid to the left, so that the probe holder 68 is pushed down to the first set position and the contact pins 71a are drawn apart from the electrodes of the plate member 200. When the holder shifting table 57 is further slid to the left, the magnet 60 fixed to the projected portion 59 of the holder shifting table 57 is abutted to the magnet 62 fixed to the projected portion 61 of the holder 51, thereafter the holder 51 having the plate member 200 set therein is shifted from the measurement position to the left as the holder shifting table 57 is shifted to the left. When the holder 51 is shifted to the left end discharge position, the measurement finished plate 200 set in the holder 51 drops down through an opening 72b defined in the left portion of the top plate member 72 so as to be discharged through an exhauster.
As described above, in this conventional analyzer device, after the drops of the solutions are disposed in the plate 200, the bar code depicted on the underside of the plate 200 is read by the bar code reading sensor 64. Therefore, even in the cases that, a plate 200 for measuring other kinds of ion concentration than that of the ion concentration to be measured is set, a plate 200 of other batch than the predetermined batch registered in the device is set, or a plate 200 is set in the inverted direction, it is not found that the measurement is unavailable until the bar code is read by the bar code reading sensor 64 after the drops of the test solutions are disposed in the plate 200. Since the plate 200 having drops of solutions disposed thereon can not be used once more, the plate 200 is spoiled. Moreover, when such a miss of the measurement is found, since the plate 200 has been shifted to the measurement position, there is a fault that it takes much time to shift the plate 200 back to the start position, resulting in deterioration of the working efficiency.